/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 1999-2005 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: TreeWalker.java,v 1.1.4.1 2005/09/08 10:58:44 suresh_emailid Exp $
 */
package com.sun.org.apache.xml.internal.serializer;

import com.sun.org.apache.xalan.internal.utils.SecuritySupport;
import java.io.File;

import com.sun.org.apache.xml.internal.serializer.utils.AttList;
import com.sun.org.apache.xml.internal.serializer.utils.DOM2Helper;
import org.w3c.dom.Comment;
import org.w3c.dom.Element;
import org.w3c.dom.EntityReference;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.ProcessingInstruction;
import org.w3c.dom.Text;

import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.helpers.LocatorImpl;

/**
 * This class does a pre-order walk of the DOM tree, calling a ContentHandler
 * interface as it goes.
 *
 * This class is a copy of the one in com.sun.org.apache.xml.internal.utils.
 * It exists to cut the serializers dependancy on that package.
 *
 * @xsl.usage internal
 */

public final class TreeWalker {

  /**
   * Local reference to a ContentHandler
   */
  final private ContentHandler m_contentHandler;
  /**
   * If m_contentHandler is a SerializationHandler, then this is
   * a reference to the same object.
   */
  final private SerializationHandler m_Serializer;

  // ARGHH!!  JAXP Uses Xerces without setting the namespace processing to ON!
  // DOM2Helper m_dh = new DOM2Helper();

  /**
   * DomHelper for this TreeWalker
   */
  final protected DOM2Helper m_dh;

  /**
   * Locator object for this TreeWalker
   */
  final private LocatorImpl m_locator = new LocatorImpl();

  /**
   * Get the ContentHandler used for the tree walk.
   *
   * @return the ContentHandler used for the tree walk
   */
  public ContentHandler getContentHandler() {
    return m_contentHandler;
  }

  public TreeWalker(ContentHandler ch) {
    this(ch, null);
  }

  /**
   * Constructor.
   *
   * @param contentHandler The implemention of the contentHandler operation (toXMLString, digest,
   * ...)
   */
  public TreeWalker(ContentHandler contentHandler, String systemId) {
    // Set the content handler
    m_contentHandler = contentHandler;
    if (m_contentHandler instanceof SerializationHandler) {
      m_Serializer = (SerializationHandler) m_contentHandler;
    } else {
      m_Serializer = null;
    }

    // Set the system ID, if it is given
    m_contentHandler.setDocumentLocator(m_locator);
    if (systemId != null) {
      m_locator.setSystemId(systemId);
    } else {
      try {
        // Bug see Bugzilla  26741
        m_locator.setSystemId(
            SecuritySupport.getSystemProperty("user.dir") + File.separator + "dummy.xsl");
      } catch (SecurityException se) {// user.dir not accessible from applet
      }
    }

    // Set the document locator
    if (m_contentHandler != null) {
      m_contentHandler.setDocumentLocator(m_locator);
    }
    try {
      // Bug see Bugzilla  26741
      m_locator.setSystemId(
          SecuritySupport.getSystemProperty("user.dir") + File.separator + "dummy.xsl");
    } catch (SecurityException se) {// user.dir not accessible from applet

    }
    m_dh = new DOM2Helper();
  }

  /**
   * Perform a pre-order traversal non-recursive style.
   *
   * Note that TreeWalker assumes that the subtree is intended to represent
   * a complete (though not necessarily well-formed) document and, during a
   * traversal, startDocument and endDocument will always be issued to the
   * SAX listener.
   *
   * @param pos Node in the tree where to start traversal
   */
  public void traverse(Node pos) throws org.xml.sax.SAXException {

    this.m_contentHandler.startDocument();

    Node top = pos;

    while (null != pos) {
      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode) {
        endNode(pos);

        if (top.equals(pos)) {
          break;
        }

        nextNode = pos.getNextSibling();

        if (null == nextNode) {
          pos = pos.getParentNode();

          if ((null == pos) || (top.equals(pos))) {
            if (null != pos) {
              endNode(pos);
            }

            nextNode = null;

            break;
          }
        }
      }

      pos = nextNode;
    }
    this.m_contentHandler.endDocument();
  }

  /**
   * Perform a pre-order traversal non-recursive style.
   *
   * Note that TreeWalker assumes that the subtree is intended to represent
   * a complete (though not necessarily well-formed) document and, during a
   * traversal, startDocument and endDocument will always be issued to the
   * SAX listener.
   *
   * @param pos Node in the tree where to start traversal
   * @param top Node in the tree where to end traversal
   */
  public void traverse(Node pos, Node top) throws org.xml.sax.SAXException {

    this.m_contentHandler.startDocument();

    while (null != pos) {
      startNode(pos);

      Node nextNode = pos.getFirstChild();

      while (null == nextNode) {
        endNode(pos);

        if ((null != top) && top.equals(pos)) {
          break;
        }

        nextNode = pos.getNextSibling();

        if (null == nextNode) {
          pos = pos.getParentNode();

          if ((null == pos) || ((null != top) && top.equals(pos))) {
            nextNode = null;

            break;
          }
        }
      }

      pos = nextNode;
    }
    this.m_contentHandler.endDocument();
  }

  /**
   * Flag indicating whether following text to be processed is raw text
   */
  boolean nextIsRaw = false;

  /**
   * Optimized dispatch of characters.
   */
  private final void dispatachChars(Node node)
      throws org.xml.sax.SAXException {
    if (m_Serializer != null) {
      this.m_Serializer.characters(node);
    } else {
      String data = ((Text) node).getData();
      this.m_contentHandler.characters(data.toCharArray(), 0, data.length());
    }
  }

  /**
   * Start processing given node
   *
   * @param node Node to process
   */
  protected void startNode(Node node) throws org.xml.sax.SAXException {

//   TODO: <REVIEW>
//    A Serializer implements ContentHandler, but not NodeConsumer
//    so drop this reference to NodeConsumer which would otherwise
//    pull in all sorts of things
//    if (m_contentHandler instanceof NodeConsumer)
//    {
//      ((NodeConsumer) m_contentHandler).setOriginatingNode(node);
//    }
//    TODO: </REVIEW>

    if (node instanceof Locator) {
      Locator loc = (Locator) node;
      m_locator.setColumnNumber(loc.getColumnNumber());
      m_locator.setLineNumber(loc.getLineNumber());
      m_locator.setPublicId(loc.getPublicId());
      m_locator.setSystemId(loc.getSystemId());
    } else {
      m_locator.setColumnNumber(0);
      m_locator.setLineNumber(0);
    }

    switch (node.getNodeType()) {
      case Node.COMMENT_NODE: {
        String data = ((Comment) node).getData();

        if (m_contentHandler instanceof LexicalHandler) {
          LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

          lh.comment(data.toCharArray(), 0, data.length());
        }
      }
      break;
      case Node.DOCUMENT_FRAGMENT_NODE:

        // ??;
        break;
      case Node.DOCUMENT_NODE:

        break;
      case Node.ELEMENT_NODE:
        Element elem_node = (Element) node;
      {
        // Make sure the namespace node
        // for the element itself is declared
        // to the ContentHandler
        String uri = elem_node.getNamespaceURI();
        if (uri != null) {
          String prefix = elem_node.getPrefix();
          if (prefix == null) {
            prefix = "";
          }
          this.m_contentHandler.startPrefixMapping(prefix, uri);
        }
      }
      NamedNodeMap atts = elem_node.getAttributes();
      int nAttrs = atts.getLength();
      // System.out.println("TreeWalker#startNode: "+node.getNodeName());

      // Make sure the namespace node of
      // each attribute is declared to the ContentHandler
      for (int i = 0; i < nAttrs; i++) {
        final Node attr = atts.item(i);
        final String attrName = attr.getNodeName();
        final int colon = attrName.indexOf(':');
        final String prefix;

        // System.out.println("TreeWalker#startNode: attr["+i+"] = "+attrName+", "+attr.getNodeValue());
        if (attrName.equals("xmlns") || attrName.startsWith("xmlns:")) {
          // Use "" instead of null, as Xerces likes "" for the
          // name of the default namespace.  Fix attributed
          // to "Steven Murray" <smurray@ebt.com>.
          if (colon < 0) {
            prefix = "";
          } else {
            prefix = attrName.substring(colon + 1);
          }

          this.m_contentHandler.startPrefixMapping(prefix,
              attr.getNodeValue());
        } else if (colon > 0) {
          prefix = attrName.substring(0, colon);
          String uri = attr.getNamespaceURI();
          if (uri != null) {
            this.m_contentHandler.startPrefixMapping(prefix, uri);
          }
        }
      }

      String ns = m_dh.getNamespaceOfNode(node);
      if (null == ns) {
        ns = "";
      }
      this.m_contentHandler.startElement(ns,
          m_dh.getLocalNameOfNode(node),
          node.getNodeName(),
          new AttList(atts, m_dh));
      break;
      case Node.PROCESSING_INSTRUCTION_NODE: {
        ProcessingInstruction pi = (ProcessingInstruction) node;
        String name = pi.getNodeName();

        // String data = pi.getData();
        if (name.equals("xslt-next-is-raw")) {
          nextIsRaw = true;
        } else {
          this.m_contentHandler.processingInstruction(pi.getNodeName(),
              pi.getData());
        }
      }
      break;
      case Node.CDATA_SECTION_NODE: {
        boolean isLexH = (m_contentHandler instanceof LexicalHandler);
        LexicalHandler lh = isLexH
            ? ((LexicalHandler) this.m_contentHandler) : null;

        if (isLexH) {
          lh.startCDATA();
        }

        dispatachChars(node);

        {
          if (isLexH) {
            lh.endCDATA();
          }
        }
      }
      break;
      case Node.TEXT_NODE: {
        //String data = ((Text) node).getData();

        if (nextIsRaw) {
          nextIsRaw = false;

          m_contentHandler
              .processingInstruction(javax.xml.transform.Result.PI_DISABLE_OUTPUT_ESCAPING, "");
          dispatachChars(node);
          m_contentHandler
              .processingInstruction(javax.xml.transform.Result.PI_ENABLE_OUTPUT_ESCAPING, "");
        } else {
          dispatachChars(node);
        }
      }
      break;
      case Node.ENTITY_REFERENCE_NODE: {
        EntityReference eref = (EntityReference) node;

        if (m_contentHandler instanceof LexicalHandler) {
          ((LexicalHandler) this.m_contentHandler).startEntity(
              eref.getNodeName());
        } else {

          // warning("Can not output entity to a pure SAX ContentHandler");
        }
      }
      break;
      default:
    }
  }

  /**
   * End processing of given node
   *
   * @param node Node we just finished processing
   */
  protected void endNode(Node node) throws org.xml.sax.SAXException {

    switch (node.getNodeType()) {
      case Node.DOCUMENT_NODE:
        break;

      case Node.ELEMENT_NODE:
        String ns = m_dh.getNamespaceOfNode(node);
        if (null == ns) {
          ns = "";
        }
        this.m_contentHandler.endElement(ns,
            m_dh.getLocalNameOfNode(node),
            node.getNodeName());

        if (m_Serializer == null) {
          // Don't bother with endPrefixMapping calls if the ContentHandler is a
          // SerializationHandler because SerializationHandler's ignore the
          // endPrefixMapping() calls anyways. . . .  This is an optimization.
          Element elem_node = (Element) node;
          NamedNodeMap atts = elem_node.getAttributes();
          int nAttrs = atts.getLength();

          // do the endPrefixMapping calls in reverse order
          // of the startPrefixMapping calls
          for (int i = (nAttrs - 1); 0 <= i; i--) {
            final Node attr = atts.item(i);
            final String attrName = attr.getNodeName();
            final int colon = attrName.indexOf(':');
            final String prefix;

            if (attrName.equals("xmlns") || attrName.startsWith("xmlns:")) {
              // Use "" instead of null, as Xerces likes "" for the
              // name of the default namespace.  Fix attributed
              // to "Steven Murray" <smurray@ebt.com>.
              if (colon < 0) {
                prefix = "";
              } else {
                prefix = attrName.substring(colon + 1);
              }

              this.m_contentHandler.endPrefixMapping(prefix);
            } else if (colon > 0) {
              prefix = attrName.substring(0, colon);
              this.m_contentHandler.endPrefixMapping(prefix);
            }
          }
          {
            String uri = elem_node.getNamespaceURI();
            if (uri != null) {
              String prefix = elem_node.getPrefix();
              if (prefix == null) {
                prefix = "";
              }
              this.m_contentHandler.endPrefixMapping(prefix);
            }
          }
        }
        break;
      case Node.CDATA_SECTION_NODE:
        break;
      case Node.ENTITY_REFERENCE_NODE: {
        EntityReference eref = (EntityReference) node;

        if (m_contentHandler instanceof LexicalHandler) {
          LexicalHandler lh = ((LexicalHandler) this.m_contentHandler);

          lh.endEntity(eref.getNodeName());
        }
      }
      break;
      default:
    }
  }
}  //TreeWalker
